The Mekong River, which________ several countries in Southeast Asia, ______to be playing a significant role in the region.

His mother had thought that it would be good for his character to________from home and earn some money on his own

Thanks for listening to my problem and giving me your advice, Amy.—_______. That’s what friends are for.

Who ______ it be that is singing in the next room?— It _______ be Lucy, but I am not sure.

have you studied in this school —For about two years.